The use of decorative glass in houses and other structures is well known. Such decorative glass includes stained or leaded glass windows of the type comprising a plurality of tinted and clear pieces of glass arranged in an artistic pattern. In some cases, the peripheral edge of one or more of the pieces of glass is beveled.
Under certain light conditions, light rays intersecting the beveled portions of discrete glass pieces of a stained glass window will be refracted so as to form "light patterns" on a surface, e.g., a wall, positioned near the window. As used herein, "light patterns" refers to visually discernible patterns formed on a surface by a light-refracting device. Such patterns are often slightly darker than the surface on which they are projected, and under certain circumstances such patterns may have an intense, dazzling appearance. Under certain circumstances such patterns may have an intense, dazzling appearance. Under certain conditions, the light patterns formed by discrete glass pieces of a stained glass window may include all or a portion of the visible color spectrum. Light patterns of the type formed by known stained glass windows typically lack any identifiable pattern and often include discrete light portions which are separated from one another. Thus, the overall effect of the light patterns formed by known stained glass windows is typically characterized by disarray and absence of recognizable shapes and patterns.
Glass and other sheets of transparent material have been used in window openings, as well as in conjunction with artificial lighting fixtures, to diffuse light incident thereon or to refract and transmit incident light which would otherwise be reflected. For instance, U.S. Pat. Nos. 595,273, 1,277,065, and 1,669,663 disclose light-refracting sheet glass designed to refract, and transmit as diffused light, the light rays intersecting the outer surface of the glass. Such glass includes a plurality of concave or convex sections arranged in a regular geometric pattern on one surface of the glass. In addition, the glass sheet disclosed in U.S Pat. No. 595,273 is apparently designed to provide such diffusion without producing the dazzling effect which occurs when light is refracted by a conventional prism. U.S. Pat. No. 2,859,334 discloses a transparent louver designed for diffusing light emitted by a fluorescent lighting fixture. One embodiment of the louver comprises a series of four-sided pyramid-like projections arranged in a regular geometric pattern, with each of the projections being surrounded by an upstanding wall. To obtain satisfactory diffusion of the light generated by the associated fluorescent lighting fixture, each of the projections is about 0.375-inch square. It is also known to provide corrugated transparent sheet material for the purpose of refracting light incident on one surface thereof so that objects will appear distorted when viewed through one side of the sheet of material, as disclosed in U.S. Pat. No. 1,886,445.
Thus, known stained glass windows and known transparent sheets of material for refracting light intersecting the material so as to diffuse the light are not designed for producing artistic light patterns comprising geometric shapes arranged in discernible order on a surface proximate to the window or sheet.